Subject(s)
COVID-19 , Pandemics , Developing Countries , Humans , SARS-CoV-2 , Surveys and QuestionnairesABSTRACT
INTRODUCTION: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been caused the greatest pandemic of our century. Many of the deaths related to it are due to a systemic inflammatory response, which has been called 'cytokine storm'. OBJECTIVES: We developed a comprehensive review of the pathophysiology mechanisms of COVID-19 and of the rationale for drugs and therapeutics that have been tested in clinical trials. METHODS: A narrative review of the literature was conducted using PubMed, SciELO, Bireme, Google Scholar and ClinicalTrials. RESULTS: SARS-CoV-2 has evolutive mechanisms that made it spread all around the globe, as a higher latency period and a lesser lethality than other coronaviruses. SARS-CoV-2 causes a delay in the innate immune response and it disarranges the immune system leading to an overwhelming inflammatory reaction (the 'cytokine storm'). In this scenario, high levels of interleukins (IL), notably IL-6 and IL-1, create a positive feedback of chemokines and immune responses, and powers pulmonary and systemic tissue damage, leading to capillary leakage and SARS, the main cause of death in patients with COVID-19. On 17 July 2020, there were 1450 entries on ClinicalTrials.gov of ongoing studies on COVID-19. The mechanisms of the main therapeutic approaches were comprehensively reviewed throughout the text. Therapies focus on blocking viral entry (remdesivir, umifenovir, among others) and blocking of immune system for cytokine storm control (IL-1 and IL-6 inhibitors, glucocorticoids, convalescent plasma, among others). CONCLUSIONS: Understanding of action mechanisms of SARS-CoV-2 enables us to direct efforts on effective therapeutic targets. This comprehensive review helps to interpret the clinical results of the several trials ongoing.
Subject(s)
COVID-19 Drug Treatment , COVID-19/complications , COVID-19/therapy , Cytokine Release Syndrome/therapy , Cytokine Release Syndrome/virology , SARS-CoV-2/physiology , COVID-19/diagnosis , Cytokine Release Syndrome/diagnosis , HumansABSTRACT
Several viruses transmitted through saliva, such as herpes simplex virus, cytomegalovirus, and Zika virus, are capable of infecting and replicating in the oral mucosa, leading to painful oral ulcers. Few studies have described the oral manifestations of coronavirus disease 2019 (COVID-19). There is growing evidence that angiotensin-converting enzyme 2 (ACE2), the main host cell receptor of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is highly expressed on the epithelial cells of the tongue and of the salivary glands, which may explain the development of dysgeusia in patients with COVID-19. Hence, it is important to understand if SARS-CoV-2 can infect and replicate in oral keratinocytes and fibroblasts, causing oral ulcerations and superficial necrosis. Here, we report a series of 8 cases of COVID-19 infection, with oral necrotic ulcers and aphthous-like ulcerations which developed early in the course of disease after the development of dysgeusia and affected the tongue, lips, palate, and oropharynx. A short review of the literature regarding the important role of ACE2 in SARS-CoV-2 cellular entry is also provided, bringing new insights into oral keratinocytes and minor salivary glands as potential targets.